Special high purity silicone oil has been developed as a medical device for use in the surgical treatment of the retina. Specifically, silicone oil is used as an internal tamponade in vitreoretinal surgery. It is indicated mainly for the surgical treatment of pathological changes generated by a proliferative process such as proliferative vitreoretinopathy (PVR), retinal detachment with PVR, giant retinal tears, and traction detachment associated with diabetic retinopathy.
In use, silicone oil is injected into the patient's eye during a surgical procedure. Silicone oil is a very viscous substance and it is commercially packaged in either sterile vials or disposable syringes. If the material is packaged in vials it must be dispensed into a syringe before it can be injected. The inherent high viscosity of silicone oil makes it physically difficult to inject the material from a hand held syringe through a small needle or cannula into the eye using a standard syringe with plunger.
In order to make the injection of the material easier, various mechanical devices have been developed to assist in the injection. Most of these devices utilize air pressure to push the plunger or stopper of a syringe. However, in order to use any of these devices the silicone oil must first be poured from the commercial container in which it is delivered into a syringe designed to fit the mechanical injection device. The pneumatic injection devices that have been developed to date, do not allow the user to inject the silicone oil or other viscous fluids directly from the syringe in which it is commercially delivered.
Therefore it would be very advantageous to provide a device for dispensing silicone oil or other viscous fluid which allows the user to inject the viscous material directly without the need to pour the fluid into a second container from the vial or syringe in which it is purchased into a new syringe designed to fit a mechanical injection device which overcomes this problem.